Can injectors cause KR?

[Squid4life]

That may sound like an odd question but my 42.5's are about the only thing that has always been with my car since it has been up and running and I have always had KR. I have tried ECM's, chips, MAF's, coil packs, new vac hose with zip ties, etc, etc, etc. I always seem to get KR, have ever since my conversion to IC, and pretty sure it was even before that. I have a chip from Eric at TT, so I am sure chip is not an issue. The injectors were given to me from a friend because he went bigger and always had the tip in stumble. My car always smells rich at idle, and I get KR on the gauge and audible when easing up to 10+ psi of boost. I have Razor alky, but I still get KR. At first I thought it was false but lately I have heard it when the conditions are right. (I have loud ass exhaust so hard to hear somtimes...)

My question is: can my 42.5's have anything to do with my KR? I am about ready to swap them out for some 60's and a TT chip. Any input? I am ready to get this thing running right since I just got back from 6 months in the gulf.

 

[Chuck Leeper]

"My question is: can my 42.5's have anything to do with my KR? I am about ready to swap them out for some 60's and a TT chip. Any input?".

Absolutely can. I just did a set of them that were several yrs old. What a mess! They were so far out of range, leaked, poor patterns, that I could not get them back to a useful set.
I think you are on the right track. A TT chip, and a set of 60's, and don't look back.

 

[t3intercooled]

Yes injectors can cuase knock retard. I also have the 42.5s and since i ported my stock heads, went to an 70mm upper plenum and 70mm throttle body, those injectors are way to small. My motor is pushing in too much air. I personally would go with the 75 lb per hour injectors. You can get an upgraded chikp from eric and he sells those injectirs as well for only 359.00. I would also look at investing in the powerlogger from full throttle for 249.99, real nice way of telling where exactly your knock retard is and en even better way to tune it right. PM me if you have any questions about the poerlogger and such.

 

[TurboMonte 2]

Or, you can pull your injrs, send to Chuck for a cleaning/flow-testing & see where YOU really stand (about $90-100?--ck w/ Chuck). I'm sure Chuck has some "decent 42.5#'ers" lying around he could let you have for cheap to replace any bad one(s)--or you could probably buy any needed new ones for $35'ish.

But, if you have $300+ for new 60#'ers & another $100'ish for matching TTwk chip, and don't want your car out of service for 7-10 days--that's definitely the way to go...

I'm OK w/ my 42.5 (or should I more-precisely say 42.3) #'ers & 23# boost on alky for now, but I've got to be getting close to max duty cycle.

 

[INEEDAGN]

Take those injectors out and smash them with a hammer. Or you can send them back to me and I will, before they cause someone to lose an engine. Should have done it when I took them out.

60's and extender extreme setup is the bomb!!

bob

 

[Squid4life]

Thanks guys for all the input. I mailed one of my chips in yesterday to Eric to burn for the 60's and will be getting them within the next week or so once the banker (AKA wifey) releases the funds. I sure hope this takes care of the issue. I have been driving this car easy for the past few years trying to troubleshoot as time allows. I kind of hate having such a picky car as a daily.

Bob, that is most likely what I will do, either that or offer them up as "cores" if someone wants to get them flowed and checked out. I am scared to mess with them though. They worked for what I needed them for I suppose, so I really can't complain too bad. They made it from Kansas to P'Cola, then out here to San Diego.

Thanks again guys for the input, I will post results as soon as I get the chip and injectors in and tested.

 

[Squid4life]

60's are on order and I sent one of my chips back to Eric to get burned for them. Now it is the waiting game...

 

[Squid4life]

Well, 60's and chip are in but still have KR in 3rd. It is not there in 2nd if I ease into it, but 3rd has KR I can hear. The 42.5's weren't the problem, at least not all of it, but the 60's sure helped with driveability. I found my DP was hitting the upper control arm, but even with that adjusted I still have KR. Car still hates me...

 

[Underboost]

I know someone who is going thru this exact problem. So far this has been changed Coil Pack, Fuel Pump, ECU, Chip, had 43.5 now trying 50's, fuel filter, all of this was done today and still knock. car runs rich at Idle and leans out when you roll on the gas. Fuel PSI is good thru out driving. You can watch the 02's lean out on the Scan Master. I have never seen anything like it. Oh the motor is stock and at 17psi boost.

 

[karst#9]

Check fuel pump and regulator. I had a problem like this,car ran good for 5-10 minutes, after that started to get knock,stumbled,popped back. I put a fuel pressure gauge on the rail with a hose and ductaped:redface: onto my windshield. I took the car out and for the first 5 or 10 minutes i was getting 1 psi fuel for one pound of boost, but after that,the fuel pressure didnt increase. Changed fuel pump,didnt help,put a new regulator and solved the problem. Even with the old regulator,fuel pressure would hold on the rail for more than an hour. I thought my injectors were bad too,i pulled them and had them checked and flow tested and they were fine.

 

[callmeebryan]

Next test..... and EGT probe/gauge... that will tell you whats going on.

 

[INEEDAGN]

Just out of curiosity is your third gear pressure switch in the trans working? It's not likely THE problem but if the computer still thinks you're in 1 or 2 it will account for a couple degrees of knock.

I'd still trash the 009s. BUT they are yours now and you can sell them or give them away if you want.

 

[karst#9]

I'll take the 009's if your throwing them away

 

[INEEDAGN]

EDIT: nevermind

 

[Squid4life]

I also have replaced coil pack, fuel pump, ECU, chip, motor mount, tranny mount, removed the exhaust totally, fuel pressure regulator, tensioner pulley, all vac hoses, IC hoses, intake gaskets, etc. My fuel pressure raises like it is supposed to. I need to buy a USB to parallel adapter so I can use my new laptop and Tlink to get some files and maybe pull timing/add fuel in 3rd and see what happens.

Where is a good and not too crazy expensive place to get an EGT gauge and probe? I have a Harbor Freight tools not too far from here, didn't they sell the multimeter style EGT gauges at one time?

How would I know if my 3rd pressure switch isn't working? Tranny is new bullet proof with a few thousand on it, shift and holds pressure fine. Not too keen on tranny's...

And the injectors are NOT available... Not worth the risk, get something like the 60's. My driveability and idle is much smoother. Car pulls like a MF'er in 2nd, like a new car.

Car may just be babied for a while. A little short on cash. Have to buy a ~$52,000 wheelchair van so we can tote my son around. He is getting to big to lift in and out of a car.

 

[Underboost]

Check timing. If you take a paper clip and jump A&B on the ALDL it will add 15 degrees of timing. Get your timing light out and check if its at the factory 15 degree mark. Just to eliminate one problem. Eric Marshall told me that.

 

[gn4u2c]

People are crazy , If you take a vote on how many people have run mid 11's on 009's for years and logged millions of miles between them all and never had a issue the list would be staggering . There is nothing wrong with a good working set of 009's proven over and over . I would definatly check them before replacing heck my local machine shop will test them and check flow for $6.00 each
I think people get caught up in this bigger is better stuff so much they lose focus throwing away countless $$, sure the vendors love it but what about your kids?? :wink: Take some time read old post check your old articles learn how to diagnose a problem not throw money on the fire hoping it will put it out. You will remember the times when 009's a te-44 and a few other bolt ons would take you mid 11's all day.

 

[karst#9]

Could be a voltage problem. Check grounds on back of head and battery. I always put an extra ground on engine made out of a battery cable.

 

[Squid4life]

gn4u2c, I agree with you to a point but I have been fighting this issue for almost two years, and one of the few things I haven't replaced was the injectors. The 42.5's weren't my total issue, but new injectors DID fix part of it, not to mention my idel quality and driveability is much better. I haven't filled up all the way and checked mileage but it seems to be lasting a bit longer too. This set of injectors have been an in two cars, mine and Bobs, (INEEDAGN) and issues in both. Bob was nice enough to give them to me for free to try and they served their daily driver purpose for a long time, but it is time to fix my KR issue.

I don't doubt some people have good luck wiht 42.5's, and go fast on them, but this exact set seems to be cursed, at least in my car.

karst- My voltage is strong and doesn't dip, and fuel pressure is very steady and strong. I have the heads on fresh metal, not paint, and have extra grounds like you suggested. (engine to frame to body)

Still working the issue in my spare time, but that is very little right now. I leave again in January for cruise.

 

[INEEDAGN]

The third gear switch I was referring to can be checked using turbolink or directscan. Turbolink has a little green light on the display that comes on when it hits third gear. Don't know if scanmaster can do it or not, but worst case scenario you can probably hook up an ohmmeter to the wire at the trans to check it.

There's a one wire pressure switch in the trans that closes when third gear is applied that sends a signal to the ecm to let it know the car is in third. Most modern chips use this feature to dial the timing back 1-3 degrees to help reduce knock due to the extra load of third gear and up.
It is possible that if this were not working it could account for 1-3 degrees of knock in third gear. Doubt it's the issue but it should be checked. Did you properly torque the knock sensor?